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Finding the Fourth Proportional to 620.25, 929.81 and 311.78

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Solution

The fourth proportional to 620.25, 929.81 and 311.78 is: 467.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.25 : 929.81 = 311.78 : x
  2. Step 2: Convert to fraction form
    620.25/929.81 = 311.78/x
  3. Step 3: Cross multiply
    620.25x = 929.81 × 311.78
  4. Step 4: Simplify right side
    620.25x = 289,889.95
  5. Step 5: Solve for x
    x = 289,889.95/620.25
  6. Step 6: Final answer
    x = 467.38

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.